Question

What is the value of $(7.5\times 7.5+37.5+2.5\times 2.5)?$

• A. $30$
• B. $60$
• C. $80$
• D. $100$

Answer 1

The correct option is D $100$

$(7.5\times 7.5+37.5+2.5\times 2.5)$

$=(7.5{)}^2+2\times 7.5\times 2.5+(2.5{)}^2$
$=(7.5+2.5{)}^2$ ....[Using $a^2+2ab+b^2=(a+b{)}^2]$

$={10}^2$

$=100$